Psychopathologists have increasingly applied experimental cognitive psychology paradigms to elucidate automatic information-processing biases associated with panic disorder. The theoretical motivation for targeting automaticity arises from the "ego-dystonic" phenomenology of panic; panic attacks appear involuntary, thereby implying that the underlying mechanisms are automatic, not strategic (i.e., involuntary, conscious, effortful). Although extant anxiety research has been incapable of distinguishing between automatic and strategic processing, recent breakthroughs in cognitive science now provide approaches for isolating automaticity. The purpose of the four experiments proposed here is to apply these methods to determine whether panic disorder is characterized by 1) automatic attentional biases for processing threat cues, 2) deficits in strategic control over attentional biases for threat, and 3) memory biases for threat. These methods include Jacoby's (1991) process- dissociation procedures, a hybrid paradigm incorporating elements of repetition priming and word naming, and a hybrid paradigm incorporating elements of repetition priming and Stroop color-naming. Control groups of normal subjects, social phobia patients, and major depressive disorder patients will reveal whether predicted cognitive biases are specific to panic disorder or whether they occur in other emotional disorders. Control stimuli of positive valence will reveal whether predicted biases are specific to information about threat or whether they extend to any emotional information. Determination of automatic attentional and memory biases for threat ought to clarify what cognitive dysfunctions figure in the maintenance of panic disorder.